In general, multi-function tools, including in a single instrument, pliers, and other selected tools, such as screwdrivers, knife blades, files and the like are well known. Many prior art multi-function tools include a main tool and several auxiliary tools. For example, in U.S. Pat. No. 4,122,569 issued on Oct. 31, 1978 to Thomas H. Hitchcock, a crescent wrench is provided with multiple tools pivotally attached to a universal joint located at an opposite end of the wrench. Other multi-function tools include a pair of cross-jaw pliers with channel-shaped handles, and a plurality of auxiliary tools that are pivotally connected to the handles. The plier jaws include respective tangs that are slidably affixed to the respective handles, so that the jaws may be slidably retracted into the handles. Examples of such multiple tools are described in U.S. Pat. Nos. 5,142,721 and 5,212,844 issued on Sep. 1, 1992 and May 25, 1993, respectively, to George C. Sessions et al.
In these multi-function tools, however, the main tool is permanently attached to the body of the multi-function tool. In certain circumstances it may be desirable to replace one main tool with another. Since only one main tool is provided in the multi-function tool, a full-size version of another tool must also be brought along, when required.
In addition, in some multi-function tools the auxiliary tools are not fully enclosed when in their retracted position, thereby providing an uneven surface for the user to grip when handling the tool. Alternatively, other multi-function tools may be equipped with a pair of handles into which the auxiliary tools are folded. This tends to make the tool bulky and difficult to manage.
Another feature present in certain multi-function tools is an integral spring formed in the region of the handle proximate the pivotally attached ancillary tools. The integral spring cooperates with a surface of each selected ancillary tool to lock the selected tool in an extended position. The selected tool is released by application of sufficient pressure to the working portion of the ancillary tool to overcome the spring force of the integral spring.
An attempt has been made, by the assignee of the present invention in U.S. Ser. No. 08/771,449 filed on Dec. 20, 1996, to provide a locking mechanism for retaining an ancillary tool in an extended, working position. The locking mechanism includes a pair of buttons for releasing the ancillary tool from the extended position. The buttons project from the top and bottom of the tool. However, this approach may increase the size of the tool beyond that desired by a user.
In light of the foregoing, it is desirable to provide a multi-function tool in which a primary implement may be easily attached to and removed from a caddy or handle. In addition, it is desirable to provide a locking mechanism for attaching the primary tool to the caddy. Another desirable feature is to provide a compact enclosure for housing the secondary tools. Moreover, it is desirable to provide a simple locking mechanism that is not susceptible to being accidentally released for retaining the secondary tools in an extended position. Finally, it is further desirable to provide a light on the multi-function tool for illuminating a work area.